Checkpoint immunotherapy for cancer: superior survival, unaccustomed toxicities

Immune Checkpoint Inhibitors and Cardiovascular Adverse Events

In the last years, we assisted to a tremendous increase in therapeutic options for the management of cancers, with immunotherapy at the forefront of this innovation. Immune checkpoint inhibitors (ICIs) have been developed to enhance the activity of the immune system against cancer cells (1) and the number of approvals for ICIs has rapidly increased. ICIs have also been associated with disinhibited cytotoxic T cells that damage healthy tissue in multiple organs, causing immune-related adverse events (AEs). Cardiovascular AEs (CVAe) are increasingly reported: myocarditis, Takotsubo syndrome, pericarditis and pericardial effusion, worsening of atherosclerosis, acute coronary syndromes, non-inflammatory heart failure, and ischaemic stroke. They are classified into five grades, based on presenting symptoms, level of cardiac biomarkers, and imaging. Even though myocarditis occurs more frequently than previously thought, clinically relevant myocarditis is a rare irAE compared to other irAE (0.5-1.2%). The clinical manifestations range from mild symptoms such as to chest pain, heart failure, and cardiogenic shock. The prognosis is severe, with mortality rates ranging from 25% to 50%. It is frequently associated with the concomitant use of combination of checkpoint inhibitors. The treatment strategies are tripartite: (i) holding ICI to prevent further toxicity, (ii) immunosuppression to alleviate inflammatory changes, and (iii) supportive therapy to address cardiac complications. Glucocorticoids represent the first-line treatment. In hemodynamically unstable patients, treatment with high-dose steroids should be initiated (intravenous methylprednisolone 1000 or 1250 mg oral methylprednisolone during 4 days). ICI-associated pericarditis can be accompanied by no/mild pericardial effusion up to cardiac tamponade. The treatment is made of nonsteroidal anti-inflammatory drugs and colchicine, corticosteroids if needed, and pericardiocentesis for the large effusions. ICIs could be continued for Grade 1 pericarditis, while temporary suspension of ICI is warranted for more severe cases. There is significant potential for accelerated atherosclerosis with ICIs as a long-term effect, but atherosclerosis-related CVAEs are not frequent, especially during treatment; increasing evidence associates ICIs with progression of atherosclerosis and increased atherosclerotic cardiovascular disease. ICIs can lead to arrhythmias: atrial fibrillation, supraventricular and ventricular tachycardias. Non-inflammatory heart failure syndrome have been observed in ICI-treated patients. Immune checkpoint inhibitors seem to be involved in the development of right ventricular dysfunction and pulmonary arterial hypertension. It is of the outmost importance to improve the collaboration among the different medical figures, such as cardiologists, oncologists, endocrinologists, and immunologists, both in clinical practice and in basic science research, to better recognize these adverse events, to understand their pathophysiological mechanisms, and to improve the overall survival and quality of life of the affected patients.

The Immune System, An Arrow into the Heart. Principles of Cardioimmunology, An Emerging Branch in Medicine

Cardioimmunology is an emerging branch of medicine whose development has been facilitated by more sophisticated diagnostic procedures. Recent studies have mainly focused on the immune response during myocardial infarction (MI), and there is evidence that both resident and external immune cells participate in acute inflammatory disease, as well as tissue remodeling. Following MI, macrophages, dendritic cells (DCs) and mast cells (MCs) are the main players in the heart. Under steady-state conditions, cardiac resident macrophages (CRMs) protect the heart against stress and infectious events, being involved in cell and matrix turnover, as well as phagocytosis of apoptotic cells. Moreover, CRMs contribute to the resolution of inflammation via release of interleukin (IL)-10, and efferocytosis of dying cells. Conversely, CCR2+ monocytederived macrophages promote inflammation in the acute phase of myocardial damage, with the release of pro-inflammatory cytokines. Conventional (c) DCs possess enhanced capacity to present antigens to T lymphocytes. In MI patient autopsies, massive infiltration of T helper (Th) cells and CDs has been detected in the myocardium. Cardiac MCs play a dual role during MI, with the production of cytokines for early inflammatory response, and the release of anti-inflammatory cytokines, IL10 and IL-13 during the resolution phase. In experimental coronary artery ligation, the myocardium is infiltrated with Th1, Th2, Th17, and T regulatory (TREG) cells, which participate in the acute inflammation. In cardiac repair, T cell reparative response is mediated by TREG cells, with improved ventricular remodeling and function post-ischemia. In this review, emphasis will be placed on the innate and adaptive immune response during and post-MI. At the same time, immunotherapy- based cardiac failure following chimeric antigen receptor T-cell and immune checkpoint inhibitory therapy will be pointed out.

Molecular Ensembles of Microbiotic Metabolites in Carcinogenesis

The mechanisms of carcinogenesis are extremely complex and involve multiple components that contribute to the malignant cell transformation, tumor growth, and metastasis. In recent decades, there has been a growing interest in the role of symbiotic human microbiota in the regulation of metabolism and functioning of host immune system. The symbiosis between a macroorganism and its microbiota has given rise to the concept of a holoorganism. Interactions between the components of a holoorganism have formed in the process of coevolution, resulting in the acquisition by microbiotic metabolites of a special role of signaling molecules and main regulators of molecular interactions in the holoorganism. As elements of signaling pathways in the host organism, bacterial metabolites have become essential participants in various physiological and pathological processes, including tumor growth. At the same time, signaling metabolites often exhibit multiple effects and impact both the functions of the host cells and metabolic activity and composition of the microbiome. This review discusses the role of microbiotic metabolites in the induction and prevention of malignant transformation of cells in the host organism and their impact on the efficacy of anticancer therapy, with special emphasis on the involvement of some components of the microbial metabolite molecular ensemble in the initiation and progression of tumor growth.

Characterization of immune checkpoint inhibitor-induced cardiotoxicity reveals interleukin-17A as a driver of cardiac dysfunction after anti-PD-1 treatment

BACKGROUND AND PURPOSE

Immune checkpoint inhibitors (ICI), such as anti-PD-1 monoclonal antibodies, have revolutionized cancer therapy by enhancing the cytotoxic effects of T-cells against tumours. However, enhanced T-cell activity also may cause myocarditis and cardiotoxicity. Our understanding of the mechanisms of ICI-induced cardiotoxicity is limited. Here, we aimed to investigate the effect of PD-1 inhibition on cardiac function and explore the molecular mechanisms of ICI-induced cardiotoxicity.

EXPERIMENTAL APPROACH

C57BL6/J and BALB/c mice were treated with isotype control or anti-PD-1 antibody. Echocardiography was used to assess cardiac function. Cardiac transcriptomic changes were investigated by bulk RNA sequencing. Inflammatory changes were assessed by qRT-PCR and immunohistochemistry in heart, thymus, and spleen of the animals. In follow-up experiments, anti-CD4 and anti-IL-17A antibodies were used along with PD-1 blockade in C57BL/6J mice.

KEY RESULTS

Anti-PD-1 treatment led to cardiac dysfunction and left ventricular dilation in C57BL/6J mice, with increased nitrosative stress. Only mild inflammation was observed in the heart. However, PD-1 inhibition resulted in enhanced thymic inflammatory signalling, where Il17a increased most prominently. In BALB/c mice, cardiac dysfunction was not evident, and thymic inflammatory activation was more balanced. Inhibition of IL-17A prevented anti-PD-1-induced cardiac dysfunction in C57BL6/J mice. Comparing myocardial transcriptomic changes in C57BL/6J and BALB/c mice, differentially regulated genes (Dmd, Ass1, Chrm2, Nfkbia, Stat3, Gsk3b, Cxcl9, Fxyd2, and Ldb3) were revealed, related to cardiac structure, signalling, and inflammation.

CONCLUSIONS

PD-1 blockade induces cardiac dysfunction in mice with increased IL-17 signalling in the thymus. Pharmacological inhibition of IL-17A treatment prevents ICI-induced cardiac dysfunction.

Combination toripalimab and bevacizumab for an elderly urothelial carcinoma patient with brain metastasis who failed rapidly after radiotherapy: a case report and literature review

Brain metastasis is a rare refractory event in patients with urothelial carcinoma. Platinum-based chemotherapy is the recommended first-line standard therapy for all metastasis urothelial carcinoma patients eligible for cisplatin or carboplatin. Patients ineligible for platinum may receive immunotherapy. No clear evidence exists that UC with brain metastasis is sensitive to immunotherapy, and the optimal treatment for patients with BM is uncertain. We evaluated the safety and efficacy of combined immunotherapy and antivascular therapy in an elderly patient with urothelial carcinoma with brain metastasis, and summarize the currently available evidence. First, she underwent a left nephrectomy and left ureterectomy and recovered well postoperatively. The postoperative pathologic findings were consistent with urothelial carcinoma. Approximately 2 years later, the patient developed impaired limb movement on the right side and underwent MRI, which revealed lesions in the left frontal lobe and suggested brain metastasis. The brain metastasis responded to local radiotherapy but progressed again in a short time. Then, the patient was administered toripalimab at 240 mg combined with bevacizumab at 300 mg every 3 weeks. After 1cycle of treatment, the patient achieved a quick response, and symptoms improved significantly. Repeat evaluation imaging demonstrated that the lesions in the brain and lung were significantly smaller and evaluation showed partial response. The treatment was well tolerated and the patient remained in partial response until the last follow-up by July 2022, 6 months after the initiation of treatment. This case suggests that immune checkpoint blockade combined with antivascular therapy might be a new possibility for patients with metastatic urothelial carcinoma, including brain metastases.

Cardiotoxicity Induced by Immune Checkpoint Inhibitors: What a Cardio-Oncology Team Should Know and Do

Immune checkpoint inhibitors (ICIs) have revolutionized the therapeutic scenario for several malignancies. However, they can be responsible for immune-related adverse events (irAEs), involving several organs, with a pooled incidence ranging between 54% and 76%. The frequency of cardiovascular system involvement is <1%. Among the cardiovascular irAEs, myocarditis is the most common and the most dangerous but other, less common manifestations of ICI-related cardiotoxicity include pericardial disease, arrhythmias, Takotsubo-like syndrome, and acute myocardial infarction, all of which remain poorly explored. Both oncologists and cardiologists, as well as the patients, should be aware of the possible occurrence of one or more of these complications, which in some cases are fatal, in order to implement effective strategies of cardiac surveillance. In this review, we summarize the latest studies and recommendations on the pathogenesis, clinical manifestation, diagnosis, and management of ICI-related cardiotoxicity in order to realize a complete and updated overview on the main aspects of ICI-related cardiotoxicity, from surveillance to diagnosis to management, useful for both oncologists and cardiologists in their clinical practice. In particular, in the first part of the review, we realize a description of the pathogenetic mechanisms and risk factors of the main cardiovascular irAEs. Then, we focus on the management of ICI-related cardiotoxicity by analyzing five main points: (1) identifying and evaluating the type and severity of the cardiotoxicity; (2) deciding whether to withhold ICI therapy; (3) initiating steroid and immunosuppressive therapy; (4) starting conventional cardiac treatment; and (5) restarting ICI therapy. Finally, we discuss the existing evidence on surveillance for ICI-related cardiotoxicity and propose a surveillance strategy for both short- and long-term cardiotoxicity, according to the most recent guidelines.

Hypophysitis induced by anti-programmed cell death protein 1 immunotherapy in non-small cell lung cancer: Three case reports

BACKGROUND

Hypophysitis induced by programmed cell death 1 protein (PD-1) immune checkpoint inhibitors is rare and poorly described. We report three patients with non-small cell lung cancer who developed hypophysitis after anti-PD-1 immunotherapy.

CASE SUMMARY

Both case 1 and case 2 presented with common symptoms of fatigue, nausea, and vomiting. However, case 3 showed rare acute severe symptoms such as hoarse voice, bucking, and difficulty in breathing even when sitting. Following two cycles of immunotherapy in case 3, the above severe symptoms and pituitary gland enlargement were found on magnetic resonance imaging at the onset of hypophysitis. These symptoms were relieved after 10 d of steroid treatment. Case 3 was the first patient with these specific symptoms, which provided a new insight into the diagnosis of hypophysitis. In addition, we found that the clinical prognosis of patients with hypophysitis was related to the dose of steroid therapy. Case 3 was treated with high-dose hormone therapy and her pituitary-corticotropic axis dysfunction returned to normal after more than 6 mo of steroid treatment. Cases 1 and 2 were treated with the low-dose hormone, and dysfunction of the pituitary-corticotropic axis was still present after up to 7 mo of steroid treatment.

CONCLUSION

The clinical symptoms described in this study provide a valuable reference for the diagnosis and treatment of immune-related hypophysitis.

Imaging features of toxicities associated with immune checkpoint inhibitors

The past decade has witnessed a change in landscape of cancer management with the advent of precision oncology. Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment and have played an important role in improving patient survival. While the patients are living longer, treatment with ICIs are sometimes associated with adverse effects, some of which could be fatal. Radiologists can play a crucial role by early identification of some of these adverse effects during restaging scans. Our paper focuses on the imaging features of commonly occurring ICI toxicities based on organ system.

Efficacy of chemotherapy combined with toripalimab in PD-L1-positive and high tumor mutation burden pancreatic acinar cell carcinoma: case report

BACKGROUND

Pancreatic acinar cell carcinoma (PACC) is a rare tumor, accounting for about 1% of all pancreatic exocrine cancers. Consensus on the management of metastatic PACC remains unclear.

CASE PRESENTATION

Starting from April 2019, a patient first received chemotherapy with two cycles of gemcitabine and nab-paclitaxel and two cycles of SOX regimen. After progression of disease evaluated based on RECIST 1.1, toripalimab and SOX regimen was administered because of PD-L1-positive expression, high tumor mutation burden (TMB), and somatic FANCA deletion in the tumor. Both the primary and metastatic tumor mass shrank significantly after two courses. The patient exhibited sustained partial response for at least six courses with well-controlled toxic effects. Then the treatment had to be stopped for 2 months because of the coronavirus disease 2019 pandemic. Computed tomography scan in March 2020 showed disease progression. Time from initiating treatment to tumor progression on toripalimab and SOX regimen treatment took up to at least 8 months.

CONCLUSIONS

We present the first case report where a PD-L1 positive, high TMB, and FANCA-deleted pancreatic acinar cell carcinoma was treated using chemotherapy combined with immunotherapy, in which the patient exhibited satisfactory response and tolerance.

Treatment of corticosteroid refractory immune checkpoint inhibitor myocarditis with Infliximab: a case series

Background

Glucocorticoid treatment remains the cornerstone of therapy for immune checkpoint inhibitor (ICI) myocarditis, but data supporting the use of additional immunotherapy for steroid refractory cases remains limited. We investigate the safety and efficacy of infliximab in patients with ICI myocarditis who are refractory to corticosteroids. Additionally, we highlight the importance of a multi-disciplinary approach in the care for these complex patients.

Methods

We retrospectively identified consecutive patients who developed ICI myocarditis at our institution between January 2017 and January 2020. Baseline characteristics, laboratory data and clinical outcomes were compared between patients who received infliximab and those who did not.

Results

Of a total of 11 patients who developed ICI myocarditis, 4 were treated with infliximab. Aside from age, there were no significant differences in baseline patient characteristics between the two groups including total number of ICI doses received and duration from initial ICI dose to onset of symptoms. The time to troponin normalization was 58 vs. 151.5 days (p = 0.25). The duration of prednisone taper was longer in the infliximab group (90 vs. 150 days p = 0.32). All patients survived initial hospital admission. Over a median follow-up period of 287 days, two of the 4 patients died from sepsis 2 and 3 months after initial treatment of their myocarditis; one of these patients was on a steroid taper and the other patient had just completed a steroid taper.

Conclusions

Infliximab, despite its black box warning in patients with heart failure, may be a safe and effective treatment for ICI myocarditis.

Oncological Emergencies from Pathophysiology and Diagnosis to Treatment: A Narrative Review

Oncological emergencies are defined as any acute possible morbid or life-threatening events in patients with cancer either because of the malignancy or because of their treatment. These events may occur at any time during malignancy, from symptoms present to end-stage disease. The aim of this study is the review of urgent conditions results from cancer or cancer treatment side effects that need to be addressed immediately. In this study, a comprehensive and in-depth narrative review was carried out by searching the databases of PubMed, Scopus, Science Direct, Google Scholar with the keywords of "cancer, emergency, metabolic emergency, neutropenic fever" along with the words, "tumor lysis syndrome, chemotherapeutic emergency, diagnosis, treatment " in last two decades. Patients suffering from cancer mostly face the challenges that we are classified in different categories, including metabolic, hematologic, cardiovascular, neurologic, respiratory, infectious, and chemotherapeutic emergencies. These patients mostly complain of headaches, nausea, pain, and fever. In conclusion, knowledge of oncology emergencies and palliative care as part of a team approach is critical for treating cancer patients. In this light, it is pivotal for physicians to focus on the early detection of oncological emergencies. Moreover, training programs for cancer patients help them to timely recognize and report the oncologic emergency symptoms, leading to avoid deleterious consequences and unnecessary healthcare costs as well as improve the quality of life in these patients.

TIDieR checklist evaluation of clinical trial intervention reporting for recent FDA-approved anticancer medications

IMPORTANCE

Clear and comprehensive descriptions of clinical trial interventions are necessary to translate new results into clinical practice. The TIDieR checklist was developed to be a minimum set of key items considered essential to high-quality reporting of clinical trial interventions.

OBJECTIVE

To determine the quality of reporting of recent Food and Drug Administration (FDA)-approved oncology interventions.

DESIGN

Cross-sectional investigation.

SETTING/PARTICIPANTS/INTERVENTION

Recent, FDA-approved haematology/oncology anticancer interventions.

MAIN OUTCOME MEASURE

Quality of reporting.

RESULTS

Across all included trials (n=96), a median of 8-9 (out of 12) TIDieR items were reported. Seven TIDieR items had >90% adherence, including individual-level and study-level modifications of drugs and dosing schedules. Three items were less often reported: intervention provider, including training and expertise (7/192, 3.6%); trial institution infrastructure (0/192, 0.0%); and how intervention compliance was assessed (59/192, 30.7%). Publication of a protocol improved intervention reporting (p<0.001).

CONCLUSIONS

In this analysis of clinical trials of recent, FDA-approved anticancer interventions, we found good adherence to the TIDieR checklist. These studies were homogeneous in their structure and included information; some TIDieR items were always or never/rarely reported. Clinical trial effect sizes may not translate to real-world practice for a number of reasons. Thus, to aid the translation of trial effect sizes to real-world practice, we recommend authors adhere to the TIDieR checklist and describe the infrastructure of trial centres and describe who provided the intervention, along with their expertise.

iRECIST: how to do it

Background

iRECIST for the objective monitoring of immunotherapies was published by the official RECIST working group in 2017.

Main body

Immune-checkpoint inhibitors represent one of the most important therapy advancements in modern oncology. They are currently used for treatment of multiple malignant diseases especially at advanced, metastatic stages which were poorly therapeutically accessible in the past. Promising results of recent studies suggest that their application will further grow in the near future, particularly when used in combination with chemotherapy. A challenging aspect of these immunotherapies is that they may show atypical therapy response patterns such as pseudoprogression and demonstrate a different imaging spectrum of adverse reactions, both of which are crucial for radiologists to understand. In 2017 the RECIST working group published a modified set of response criteria, iRECIST, for immunotherapy, based on RECIST 1.1 which was developed for cytotoxic therapies and adapted for targeted agents.

Conclusion

This article provides guidance for response assessment of oncologic patients under immunotherapy based on iRECIST criteria.

Cardiovascular Toxicities of Immune Checkpoint Inhibitors: JACC Review Topic of the Week

Immune checkpoint inhibitors (ICIs) have been an important therapeutic advance in the field of cancer medicine, resulting in a significant improvement in survival of patients with advanced malignancies. Recent reports provided greater insights into the incidence of cardiovascular adverse events (CVAEs) with ICI use. Myocarditis is the most common CVAE associated with ICI. Pericardial diseases, Takotsubo syndrome, arrhythmias, and vasculitis constitute other significant AEs. Physicians should be aware of these infrequent, but potentially fatal toxicities associated with ICIs as their therapeutic use becomes widespread with a myriad of approvals by the U.S. Food and Drug Administration. Management involves prompt administration of high-dose corticosteroids and discontinuation of ICIs in severe myocarditis. This review summarizes the most updated evidence on epidemiology, pathophysiological mechanisms, and management strategies of various CVAEs associated with ICIs. Highlights from recent guidelines published by National Comprehensive Cancer Network on ICI-related CV toxicities have also been incorporated.

Cancer immunotherapy-associated hypophysitis

The advances in cancer therapy have included the development of drugs that inhibit immune checkpoint ligands. Two types of immune checkpoint inhibitors, both antibodies that target CTLA-4 and PD-1, have been approved for its use in NSCLC and melanoma as first-line or second-line therapy. Sadly, not desirable consequences of immunotherapy are immune-related adverse events. immune-related hypophysitis is the most common endocrine adverse event after thyroid disfunction. The particularity of endocrine immune-related adverse events is their non-reversibility, with incidence and prevalence destined to increase in the coming years, particularly if this form of therapy is used in the future for earlier stages of cancer. Therefore, hypophysitis represents a challenge for the physician, sometimes occurring without specific symptomatology and which should be considered for clinical management. In this review, we describe the current data regarding the pathophysiology and management for immune-related hypophysitis.

[Radiological response assessment of modern immunotherapy using iRECIST]

CLINICAL/METHODICAL ISSUE

Modern immunotherapies in oncology show tumor response patterns differing from conventional chemotherapies including initial pseudo-progression.

STANDARD RADIOLOGICAL METHODS

Response evaluation criteria in solid tumors (RECIST 1.1) represent the currently most used response criteria for conventional chemotherapy of solid tumors. However, atypical response patterns of immunotherapies are not correctly classified using RECIST 1.1 so that the effectiveness is also incorrectly interpreted.

METHODICAL INNOVATIONS

In order to correctly interpret these atypical response patterns, special immune-related response criteria in solid tumors (iRECIST) have been published. In contrast to RECIST 1.1 according to iRECIST an initially unconfirmed progressive disease (iUPD) requires confirmation (iCPD) in clinically stable patients by subsequent control imaging after 4-8 weeks. New lesions are separately assessed within iRECIST.

PERFORMANCE

The iRECIST procedure allows a standardized objective assessment of a possible pseudo-progression which can occur in up to 10% of cases depending on the immunomodulating drug and tumor entity.

ACHIEVEMENTS

In principle, iRECIST was developed only for usage in trials testing modern immunotherapeutics.

PRACTICAL RECOMMENDATIONS

The iRECIST procedure might also be helpful as an additional objective response criterium for clinical treatment decisions, taking the limitations into account.

Abscopal Effect in Non-injected Tumors Achieved with Cytokine-Armed Oncolytic Adenovirus

Cancer treatment with local administration of armed oncolytic viruses could potentially induce systemic antitumor effects, or the abscopal effect, as they self-amplify in tumors, induce danger signaling, and promote tumor-associated antigen presentation. In this study, oncolytic adenovirus coding for human tumor necrosis factor alpha (TNF-α) and interleukin-2 (IL-2) Ad5/3-E2F-d24-hTNF-α-IRES-hIL-2 (also known as [a.k.a.] TILT-123) provoked antitumor efficacy in tumors that were injected with Ad5/3-E2F-d24-hTNF-α-IRES-hIL-2 and those that were left non-injected in the same animal. Importantly, the virus was able to travel to distant tumors. To dissect the effects of oncolysis and cytokines, we studied replication-incompetent viruses in mice. Systemic antitumor effects were similar in both models, highlighting the importance of the arming device. The cytokines induced positive changes in immune cell infiltrates and induced the expression of several immune-reaction-related genes in tumors. In addition, Ad5/3-E2F-d24-hTNF-α-IRES-hIL-2 was able to increase homing of adoptively transferred tumor-infiltrating lymphocytes into both injected and non-injected tumors, possibly mediated through chemokine expression. In summary, local treatment with Ad5/3-E2F-d24-hTNF-α-IRES-hIL-2 resulted in systemic antitumor efficacy by inducing immune cell infiltration and trafficking into both treated and untreated tumors. Moreover, the oncolytic adenovirus platform had superior systemic effects over replication-deficient vector through spreading into distant tumors.

Severe Psoriasis Flare After Anti-Programmed Death Ligand 1 (PD-L1) Therapy for Metastatic Non-Small Cell Lung Cancer (NSCLC)

Immunomodulatory agents that target PD-1 and its ligand (PD-L1) are being increasingly used in the management of lung cancer. Potential immune-related adverse events include dermatological complications which mostly are of low grade severity. The use of immune checkpoint inhibitors may lead to the exacerbation of autoimmune conditions. We report a case of a documented psoriasis flare with anti-PD-1 treatment for lung cancer.

Patent trend and competitive analysis of cancer immunotherapy in the United States

Immunotherapy has brought high hopes for cancer treatment, and attracted tremendous resources from the biopharmaceutical community. Here we analyze cancer immunotherapy-related patents granted by the United States Patent and Trademark Office in the past decade (2006-2016). A total of 2,229 patents were identified in 13 subfields. The growth of patent number in this field has outpaced the background rate, with cytokine-related therapies, immune checkpoint inhibitors, and natural killer cell therapies growing the most rapidly. The top 15 assignees possess 27.6% (616) of the patents. Amgen is the largest patent holder, followed by Novartis, and then by Chugai Seiyaku. The top assignees have focused on different subfields, and collaborated with each other for technology development. Our competitive analysis reveals that Novartis, Chugai Seiyaku, and Abbvie lead in both patent number and average quality of patents. Meanwhile, Immunomedics owns a high-quality though relatively small patent portfolio in single-chain variable fragment technology, which is not the focus of the abovementioned forerunners. Overall, our analysis illustrates an ecosystem where industry giants and smaller-size players each occupies a niche. Selection and succession are expected to continue for years in this young ecosystem.

TNFR2: A Novel Target for Cancer Immunotherapy

Immune checkpoint inhibitors (ICIs) have revolutionized cancer therapy but exhibit variable efficacy and relapse and can induce autoimmunity. Tumor necrosis factor (TNF) receptor 2 (TNFR2) is a signaling molecule found on the surface of a subset of potent regulatory T cells (T_regs) that can activate the proliferation of these cells through nuclear factor kappa B (NF-κB). TNFR2 is also abundantly expressed on the surface of many human tumors. We propose that blocking TNFR2 might target abundant TNFR2⁺ tumor-infiltrating T_regs and directly kill TNFR2-expressing tumors. We also posit that TNFR2 inhibitors might potentially constitute safer and more targeted alternatives to ICI cancer treatment because the expression of TNFR2 on immune cells, concentrated in the tumor microenvironment of various cancers, appears to be more selective than that of checkpoint molecules.

Development of pH-sensitive Dextran Derivatives with Strong Adjuvant Function and Their Application to Antigen Delivery

To achieve efficient cancer immunotherapy, the induction of cytotoxic T lymphocyte-based cellular immunity is necessary. In order to induce cellular immunity, antigen carriers that can deliver antigen into cytosol of antigen presenting cells and can activate these cells are required. We previously developed 3-methyl glutarylated dextran (MGlu-Dex) for cytoplasmic delivery of antigen via membrane disruption ability at weakly acidic pH in endosome/lysosomes. MGlu-Dex-modified liposomes delivered model antigens into cytosol of dendritic cells and induced antigen-specific cellular immunity. However, their antitumor effects were not enough to complete the regression of the tumor. In this study, antigen delivery performance of dextran derivatives was improved by the introduction of more hydrophobic spacer groups next to carboxyl groups. 2-Carboxycyclohexane-1-carboxylated dextran (CHex-Dex) was newly synthesized as pH-responsive dextran derivative. CHex-Dex formed stronger hydrophobic domains at extremely weak acidic pH and destabilized lipid membrane more efficiently than MGlu-Dex. CHex-Dex-modified liposomes were taken up by dendritic cells 10 times higher than MGlu-Dex-modified liposomes and delivered model antigen into cytosol. Furthermore, CHex-Dex achieved 600 times higher IL-12 production from dendritic cells than MGlu-Dex. Therefore, CHex-Dex is promising as multifunctional polysaccharide having both cytoplasmic antigen delivery function and strong activation property of dendritic cells for induction of cellular immunity.

pH-sensitive polymer-modified liposome-based immunity-inducing system: Effects of inclusion of cationic lipid and CpG-DNA

Efficient vaccine carriers for cancer immunotherapy require two functions: antigen delivery to dendritic cells (DCs) and the activation of DCs, a so-called adjuvant effect. We previously reported antigen delivery system using liposomes modified with pH-sensitive polymers, such as 3-methylglutarylated hyperbranched poly(glycidol) (MGlu-HPG), for the induction of antigen-specific immune responses. We reported that inclusion of cationic lipids to MGlu-HPG-modified liposomes activates DCs and enhances antitumor effects. In this study, CpG-DNA, a ligand to Toll-like receptor 9 (TLR9) expressing in endosomes of DCs, was introduced to MGlu-HPG-modified liposomes containing cationic lipids using two complexation methods (Pre-mix and Post-mix) for additional activation of antigen-specific immunity. For Pre-mix, thin membrane of lipids and polymers were dispersed by a mixture of antigen/CpG-DNA. For Post-mix, CpG-DNA was added to pre-formed liposomes. Both Pre-mix and Post-mix delivered CpG-DNA to DC endosomes, where TLR9 is expressing, more efficiently than free CpG-DNA solution did. These liposomes promoted cytokine production from DCs and the expression of co-stimulatory molecules in vitro and induced antigen-specific immune responses in vivo. Both Pre-mix and Post-mix exhibited strong antitumor effects compared with conventional pH-sensitive polymer-modified liposomes. Results show that inclusion of multiple adjuvant molecules into pH-sensitive polymer-modified liposomes and suitable CpG-DNA complexation methods are important to design potent vaccine carriers.

Cancer and the microbiota

A host's microbiota may increase, diminish, or have no effect at all on cancer susceptibility. Assigning causal roles in cancer to specific microbes and microbiotas, unraveling host-microbiota interactions with environmental factors in carcinogenesis, and exploiting such knowledge for cancer diagnosis and treatment are areas of intensive interest. This Review considers how microbes and the microbiota may amplify or mitigate carcinogenesis, responsiveness to cancer therapeutics, and cancer-associated complications.